добавлен RegionManager

anvil-loader/src/main/java/mc/world/anvil/RegionManager.java

@@ -0,0 +1,44 @@
+package mc.world.anvil;
+
+import gnu.trove.map.TIntObjectMap;
+import gnu.trove.map.hash.TIntObjectHashMap;
+import lombok.extern.slf4j.Slf4j;
+import mc.core.utils.CompactedCoords;
+import org.springframework.lang.Nullable;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+@Slf4j
+class RegionManager {
+    private final Path regionFilesPath;
+    private final TIntObjectMap<Region> regions = new TIntObjectHashMap<>();
+
+    RegionManager(Path regionFilesPath) {
+        this.regionFilesPath = regionFilesPath;
+    }
+
+    @Nullable
+    public Region getRegion(int x, int z) {
+        final int xz = CompactedCoords.compressXZ(x, z);
+
+        if (regions.containsKey(xz)) {
+            return regions.get(xz);
+        } else {
+            Path regionFilePath = regionFilesPath.resolve("r." + x + "." + z + ".mca");
+            if (Files.exists(regionFilePath)) {
+                try {
+                    Region region = new Region(regionFilePath.toFile());
+                    regions.put(xz, region);
+                    return region;
+                } catch (IOException e) {
+                    log.error("load region from file", e);
+                    return null;
+                }
+            } else {
+                return null;
+            }
+        }
+    }
+}